Snap Roll Template Generation

This notebook compares a generated template snap roll to one recorded with a 2m F3A plane using Ardupilot.

The template snap is generated using the Snap principal element. Below short sections of line are also appended before and after the snap for easier comparison to the template section.

Some real snaps were recorded using Ardupilot and saved as a section csv. The sections are transformed so that the sections x axis points along the line the snap is on and the y axis is parallel to wings at the start of the section. This is done in the local_section function. The snaps are found by selecting all the discrete regions where the roll rate is above a threshold, then extending forwards and backwards a little.

The figures below compare 3D visualisations of the constructed snap to one of the flown snaps

The graph below show control inputs and axis rates for one of the flown snaps. It shows the initial elevator input to create the pitch break, then the rudder and aileron coming in together and the elevator dropping back a little for the autorotation. The axis rates roughly follow the control inputs.

The graphs below compare axis rates, alpha and beta between one of the recorded snaps and the template.